PURPOSE: To manufacture a unidirectional electric steel sheet excellent in magnetic properties by subjecting a steel to process annealing, thereafter measuring the magnetic flux density in the rolling direction of a steel sheet before finish rolling and executing finish rolling at a finish rolling temp. under specified conditions calculated based on the above value.

CONSTITUTION: Silicon steel stock contg. 0.01 to 0.06% C, 2 to 4% Si and 0.02 to 0.15% Mn and contg. total 0.005 to 0.1% of one or two kinds of S and Se is hot-rolled, and the obtd. hot rolled sheet is subjected to process annealing. After that, the magnetic flux density B8 (T) in the rolling direction of the steel sheet before finish rolling is measured, and finish rolling is executed at the finish rolling temp. T°C satisfying 2000B8-3120≤T≤2334B8-3484. The unidirectional electric steel sheet excellent in magnetic properties can be manufactured.